Racking mechanism for earth boring equipment



A ril 13, 1965 R. N. KNIGHTS 3,177,944

BACKING MECHANISM FOR EARTH BORING EQUIPMENT Filed June 1, 1960 5Sheets-Sheet l FIG.

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ATTORNEY! Ajax-i113, 1965 R. N. KNIGHTS BACKING MECHANISM FOR EARTHBORING EQUIPMENT 5 Sheets-Sheet 2 Filed June 1. 1960 Fla. 5.

A'r'rokNEYs April 13, 1965 R. N. KNlGHTS BACKING MECHANISM FOR EARTHBORING EQUIPMENT 5 Sheets-Sheet 5 Filed June 1. 1960 |NVENTOR Tch'd?) N.m, H75; BY

ATTORNEYS April 1965 R. N. KNIGHTS BACKING MECHANISM FOR EARTH BORINGEQUIPMENT Filed June 1, 1960 5 Sheets-Sheet 4 FIG. 8.

INVENT OR ATTORNEY April .3, 1965 R. N. KNIGHTS 3,177,944

RACKING MECHANISM FOR EARTH BORING EQUIPMENT FIG l3 1 I g; INVENTORRICHARD N. KNIGHTS (ZZW ATTORNEY United States Patent 3,177,944 RACKINGMECHANISM FOR EARTH BORIN E UIPMEN'I Richard N. Knights, Hucelecote,England,'assignor to Dowty Rotol Limited, Cheltenharn, England, aBritish company Filed June 1, 1960, Ser. No. 33,158 Claims priority,application Great Britain, June 2, 1959, 18,861/59 6 Claims. (Cl.166-775) This invention relates to earth boring equipment comprising aderrick having power-operated means for withdrawing or running inastring of drill pipe. The invention is particularly concerned withequipment for deep boring wherein a large number of pipe lengths have tobe unscrewed and stored as the drill string is withdrawn, or taken fromstorage and screwed on to the string when the latter is run in.

According to previous proposals the pipe lengths may either be stackedin the derrick to one side of the drill string, or stored at .the baseof the derrick. Such arrangement, however, may seriously encumber theclear working space in and around the derrick when handling the largenumber of pipelengths which are required in drilling to great depths.

The present invention provides for horizontal storage of pipe lengths toone side of and clear of the derrick. by means of a transport arm whichis pivoted towards the base of. the derrick for swinging movement in avertical plane, the outer end of the arm working between a substantiallyvertical position in which it can accept a pipe lengths from, or delivera pipe length to, a station in the derrick, and a substantiallyhorizontal position in which the arm can deliver a pipe length to, oraccept a pipe length from, a station associated with storage means atone side of the derrick.

The storage means may comprise a rack structure wherein the individualpipe lengths are stored horizontally, and a racking member which canenter into co-operation with the transport arm at the latter station,the racking member being arranged to move pipe lengths one at a time, ineither direction, between the said latter station and the severalpositions in the rack structure wherein the pipe lengths are stored.

The rack structure in which the pipelengths are stored horizontallypreferably has open ends giving free access to the screw-threaded pipeends for inspection purposes.

A drilling derrick and associated racking mechanism constructed tooperate in accordance with the invention is illustrated in theaccompanying drawings, of which:

FIGURE 1 is a side elevation of the drilling derrick except for itsupper part, and racking mechanism; f

FIGURE 1A is a side elevation of the upper part of the drilling derrick;

FIGURE 2 is a front elevation of the racking mechanism alone seen fromthe right hand side of FIGURE 1;

FIGURE 3 is an enlarged plan view of the pipe spinotf mechanism seen onthe section line III-11I of FIG- URE l;

FIGURE 4 is an enlarged detail view-of the pipe gripping jaws mounted onthe transport arm as. seen from below in FIGURE 1; and

FIGURE 5 is an enlarged detail of the free end of the racking arm shownin FIGURE '1; j

FIGURE 6 is a sectional view on the line VIVI of FIGURE 1;

FIGURE 7 is an enlarged elevation view of the spinotf mechanism in theupper part of FIGURE 1;

FIGURE '8 is a front elevation, i.e. from the left-hand side in FIGURE 1but on a larger scale, of part of the drilling derrick having liftplatforms mounted thereon together with telescopic hydraulic jacks foroperating same, the jacks on the near side of the structure being shownin section; I

FIGURE 9 is a front elevation'simila'r-to FIGURE 8 but with the liftplatforms and hydraulic jacksin dilferent positions;

FIGURE 10 is a diagrammatic drawing of the upper lift platform ona-larger scale than in FIGURES Sand 9, and in section to show mechanismhoused therein;

FIGURE 11 is a plan View of a detail of FIGURE 10;

FIGURE 12 is a diagrammatic drawing of the lower lift platform on alarger scale than in FIGURES 8 and 9, and in section to show mechanismhoused therein; and

FIGURE 13 is a sequence diagram relating to operation of the liftmechanism and spin-off mechanism.

The drilling derrick 10, FIGURE 1, comprises a lattice structureupstanding from a base platform 11 which itself is supported above theground 12 by a suitable base structure. The derrick supports at itsfront a pair of opopsedvertical channel members 8 which form guidewaysfor upper and lower lift platforms 13 and 14, see also FIGURES 8 and 9.Each platform as exemplified by platform 13 in FIGURE 6 has rollers 9 onopposite sides engaged in the guideways 8 and arranged to maintain theplatform horizontal during vertical guided move ment. The lift platforms13 and 14 are movable'independcntly along a-common vertical axis bymeans of telescopic hydraulic jacks; One pair of hydraulic jacks 6 hascylinders 6a upstanding from the base platformll and piston rods 6bfixed to the upper lift'p'latform 13. Each cylinder 6a extends withclearance through a'hole 6c in the lower lift platform 14. Another pairof hydraulic jacks 7 have piston rods 71 upstanding from the baseplatform and cylinders 7a whose lower endsar'e fixed to the lower liftplatform 14. The upper liftplatform 13 has a pair of holes 15 initthrough each of which the respective cylinder 7a can extend withclearance when the lift platforms 13 and 14 approach oneanother-closely.

I The arrangement of hydraulic jacks -6 and 7 in FIG- URI-ES 8 and 9will 'be better understood with reference to FIGURE 6 where it is seenthat the axes of the jacks intersect a transverse plane at'the cornersof a rectangle, in which the 'jack's of each pair occupy diagonalpositions. The jacks of each pair are diametrically opposed with respectto the axes of the drill pipe string.

' The upper lift platform 13'is in part'formed as ahousing 16 for slipsmechanism which can support the weight of the drill pipe string, and fora mechanism which can make and break the tool joints between thelengthsv of drill pipe. The slips mechanism 100*iso f generally knownkind comprising outer members 191 with inclined inner surfaces alongwhich inner wedge members 102 are movable to grip or to release a pipelength 24. The mechanism 100 is illustrated diagrammatically in FIGURE10 but a more developed mechanism suitable for the purpose is describedin US. Patent No. 3,029,488 ofRic'hard N. Knights. The mechanism 110comprises essentially upper and lower pipe gripping assemblies 111 and11.2 respectively. The upper assembly 111 shown in FIGURE 11 isfiseen tocomprise two jaws 113 and 114 pivoted together at' 115. The jaws can beclosed together or opened apart by a telescopic jack 116 which iscarriedby the jaw 113 and which acts through a lever'117 and link 118 to'mo'v'e the jaw llf t. 'The jaws 113 and 114 carry gripping 'blocks119whichcanthus be closed on to, or released from a connector '24a at theend of one drill pipe length 24. The pipe gripping "assembly 112 issimilar to the assembly 111 andinlpositionto' grip the connector of theadjoining drill pipe length. The pipe gripping assembly 112 is invertedwith respect to the assembly 111 and a-telescopic jack 1 20 isinterposedbetween lugs 121 on the larger jaws 113 of the respectiveassemblies 111, 112. The jack 120 lies in a transverse plane and can beextended or contracted to efliect relative turning movement of theassemblies 111, 112 about the axis of the drill pipe string for makingor breaking the usual screw joint between the drill pipe connectors.Such mechanism is described in more detail in the U.S. Patent No.3,041,901 of Richard N. Knights.

The lower lift platform 14 houses slips mechanism 105 similar to theslips mechanism 100.

The telescopic jacks 6 and 7 are operated by conventional hydraulicmeans which are not shown for the sake of simplicity of illustration.The strokes of the jacks are controlled manually or otherwise so as toenable the upper lift platform 13, when lowered, and the lower liftplatform 14, when raised, to be in proximity, see FIG- URE 9, and to bemovable together over a small part of the strokes of each pair of jacks6 and 7 so that the support of the drill pipe string can be transferredfrom the slips mechanism 105 to the slips mechanism 100 while both liftplatforms 13 and 14 are in motion. When the drill pipe string issupported by the slips mechanism 100 of the upper lift platform 13, themake and break mechanism 110 can be operated to loosen the screw jointbetween adjacent connectors 24a so that a length of pipe projectingabove the upper lift platform 13 can be fully unscrewed by spin-offmechanism which will be described. Conversely, when running in a stringof drill pipe the make and break mechanism can be operated to tightenthe screw joint between the added length of drill pipe and the drillpipe string, after which the support of the latter can be transferredfrom the slips mechanism 100 of the upper lift platform 13 to the slipsmechanism 105 of the lower lift platform 14 while the platform 13 ismoving over the end part of its downward stroke and the platform 14 ismoving over the beginning part of its downward stroke.

A pillar 17 upstanding from the upper lift platform 13, shown in FIGURES1, 3, 6 and 7 but omitted from FIG- URES 8 and 9, provides a mountingfor a tubular column 18 on which spin-off mechanism 19 is mounted foroperating co-axially with and above the make and break mechanism 110.Two brackets 21 and 22 fixed to the pillar 17 provide guide bearings formovement of the column 18 in a vertical direction, while a hydraulicjack 23 anchored to the bracket 21 acts vertically against a movablebracket 40 which is mounted on the pillar 17, see FIGURE 7. The jack 23can act through the movable bracket 40 upon the column 18 and spin-offmechanism 19 in order to lift a pipe length 24 clear of the string ofdrill pipe and the upper lift platform 13 as it is unscrewed. The upperportion of the pipe 24 is steadied by releasable locating jaws at theupper end of a tube 44 which is mounted on the column 18, these jawsbeing provided merely to prevent the upper portion of the drill pipe 24from whipping when it is rotated by the spin-off mechanism.

The spin-off mechanism shown in FIGURES 3 and 7 comprises a pair of arms25 fixed to the tube 44 which can turn on the column 18. A hydraulicjack attached to the movable bracket 40 acts horizontally against an arm44a fixed to the tube 44 to swing the arms 25 between extreme positionsof which one is shown in full lines and the other is in chain dot linesat 25'. These extreme positions correspond to the position at the sideof the drill rig at which a drill pipe may be handed over to or acceptedfrom the transfer arm (to be described), and to the central position atwhich the drill pipe may be accepted from or handed over to the stringof drill pipe. It is to be understood that the operation of the spin-offmechanism is reversible for joining of pipe lengths to the drill stringprior to tightening these joints by the make and break mechanism 110.The swinging arms 25 carry at their outer ends a pipe gripping rollerassembly 26 which is itself rotatable bodily about a vertical axis 37 inthe outer ends of the arms 25. The assembly 26 has upper and lower setsof divergent arms 27 in which are fixed the ends of vertical posts 27a.Upper and lower levers 28 pivoted on each post 27a carry the ends of apipe-engaging roller 29. Two such rollers 29 carried by the respectivelevers 28 may be closed towards each other or separated by means of twohydraulic jacks 31 which are anchored to the assembly 26 and act uponthe respective levers 28. The two rollers 29 are idling rollers free toturn about vertical axes, while a power driven spin-oft roller 32 ismounted to turn about the vertical axis 37 at the outer end of the arms25. The spin-off roller 32 is driven through a transmission belt 33a bya hydraulic motor 33, FIGURES 3 and 7, which is fixed to a bracket 44bprojecting from the tube 44.

The assembly 26 with its divergent arms 27, levers28 and hydraulic jacks31 is rotatable in the outer ends of the swinging arms 25 by a belt orchain 34 which passes around a pulley 35 mounted on the tube 44 andaround a pulley 36 which is fast with the assembly 26. The pulley 35 isprevented from turning with respect to the column 18 by a laterallyprojecting fork 35a which engages the pillar 17. The lengths of thepulley belt 34 cross over between the pulleys 35 and 36 so that swingingthe arms 25 causes the pulley 36 to turn in the same rotational sense.Swinging of the arms 25 by the hydraulic jack 30 in an anticlockwisedirection from the full line position shown in FIGURE 3 therefore causesthe belt 34 to impart an additional simultaneous anticlockwise motion tothe assembly 26. This enables the assembly 26 to approach the pipelength 24 on the axis of the drill string with the rollers 29 passing onopposite sides thereof and the driving roller 32 moving laterally intodirect engagement with it. When the assembly is swung towards the pipelength 24, the rollers 29 are held apart by the contraction of the jacks31 following which the jacks 31 are extended causing the idler rollers29 to grip the pipe length 24 against the driving roller 32.

The operation of the drilling derrick with the lift mechanism andspin-off mechanism will now be described with reference to the sequencediagram of FIGURE 13.

FIGURE 13 illustrates successive steps A-I at the commencement of pipepulling in which the lifts 13 and 14 are illustrated diagrammatically asbeing engageable with or disengaged from the string of drill pipe. Thespin-off mechanism 19 is shown associated with the upper lift 13, andthe make and break mechanism is indicated by arrows at stage D.

At stage A the lower lift 14 is closed on the drill pipe 24 below theconnectors 24a and it is rising. Meanwhile the upper lift 13 is open anddescends fully to await the approach of the lower lift 14 at stage B.Between stages B and C the lifts move together and lift 13 closes belowthe connectors 24a after which lift 14 opens so that the weight of thepipe string is transferred from the lower lift 14 to the upper lift 13.At stage C, lift 14 is at the end of its upward stroke and starts todescend while lift 13 continues to rise.

At stage D the make and break mechanism 110 is operated as previouslydescribed to loosen the screw joint between the connectors 24a, andthereafter the spin-01f mechanism 19 is operated to unscrew theconnectors 24a fully. The jack 23, FIGURE 7, is extended to lift thespin-off mechanism as the joint is unscrewed and to continue lifting theupper pipe length 24 relative to the drill string to the point, stage E,at which the upper pipe length 24 is well clear of the drill string andthe upper lift 13. The jack 30 can then be contracted to swing the arms25 and the spin-off mechanism 19 bodily away from the axis of the drillstring to bring the unscrewed pipe length 24 to the side of the drillingderrick, stage F.

The open lower lift 14 has meanwhile descended and between stages F andG it rises at the same speed as the upper lift 13. Between these stagesthe lower lift 14 closes on the drill pipe string below the tool jointof the next succeeding pipe length, after which the upper lift 13 isopened prior to its descent.

At stage G the two lifts have undergone a complete cycle and returned tothe original stage A, though the spin-off mechanism 19 now carries theunscrewed pipe length 24. At stage H the upper lift 13 has descendedfully to await the upward approach of the lower lift 14, and during thiswaiting period when it is stationary the pipe length 24 is in positionto be gripped by a transport arm 38 of racking mechanism, to bedescribed, and then released from the spin-off mechanism 19 bycontraction of the jacks 31.

It is to be understood that the sequence is reversible when running thedrill string into a bore hole, whereby a pipe length 24 delivered by thetransport arm 38 at stage I is spun on and tightened on the upper end ofthe drill pipe string between stages E and D as the drill pipe stringisv lowered.

The transport arm comprises a lattice girder 38 hinged at one end on apin 39 which is carried by a mounting bracket 41 upstanding from thebase platform 11. The transport arm 38 is swung in a vertical planebetween the upright position shown in FIGURE 2 in full lines and thehorizontal position 38' shown in chain dot lines by a hydraulic jack 42.The outer portion of the arm 33 carries two spaced pipe grips 43 theconstruction of which is diagrammatically shown in FIGURE 4. A bracket45 extending from the arm 38 carries a hinge pin 46 for two jaws 47having arcuate recesses shaped to engage the drill pipe. The two jaws 47have integral tails 48 which extend rearwardly and have a pair of togglelinks 43 connected between them. The centre pivot 51 of the togglelinkage has one member of a hydraulic jack 55 connected to it while theother member of the hydraulic jack is anchored to the hinge pin 46. Ifthe operating jack 55 is extended, the toggle formed by the links 49breaks thus drawing the tails 48 together and opening the jaws 47.Contraction of the jack 55 turns the toggle links 49 into line thusclosing the jaws 47 together. If the links 49 are slightly over top deadcentre in the contracted position of the jack 55 the jaws 47 will remainclosed in the event of a hydraulic failure thus minimizing the risk of apipe length coming adrift from the transport arm 38.

The pipe grips 43 are arranged to take over the drill pipe 24 from thespin-off mechanism 19 in the lowest position of the lift platform 13 andthe transport arm 38 is thereupon caused to swing downwardly to thehorizontal position 38'. At this point the pipe length now at 24 in astation associated with storage means at which the pipe length isarranged to be taken over by a poweroperated racking member fordepositing it in a rack structure. The racking member comprises a lowerarm 61 mounted by a pivot 62 to a base bracket 63. A hydraulic jack 64interposed between a ground anchorage 65 and an intermediate point 66 onthe inner arm 61 controls swinging movement of the latter in a verticalplane between the radii A and B. An upper arm 67 carried by pivot pin 68on the upper end of the lower arm 61, has a tail portion 69 coupled to ahydraulic jack 71 which is anchored on the pivot pin 66. The jack 71thus controls movement of the outer arm 67 in a vertical plane.

The upper arm 67 carries a pipe gripping mechanism 72 which is kept in aconstant attitude irrespective of the positions of the arms 61 and 67 bymeans of two parallelogram linkages of which the arms 61 and 67respectively form two of the long sides. The other long sides areprovided by links 73 and 74 whose effective lengths are equal to thoseof the arms 61 and 67, these lengths being interconnected by a bellcrank lever 75. The lower end of the link 73 is carried by a pivot 77 onthe base bracket 63 while the outer end of the link 74 is connected by apivot 7 8 to the pipe gripping mechanism 72.

The latter mechanism shown on a larger scale in FIG- URE 5 comprises aplate 81 having a fixed jaw 82 and a moving jaw 83 mounted thereon by apivot 84. A hydraulic jack 85 is pivotally interposed between the plate81 and a lug 86 on the jaw 83 so as to turn the latter between the fullline position shown in .thedrawing and the open position shown in chaindot line at 83'. It is-to be observed that in the open position, themoving jaw 83 is swung back far enough to allow a pipe length 24 carriedby the transport arm to move vertically downwards past the open jaw 83into a position where the latter can be closed on the pipe length by thejack85. The jaws 82 and 83 and the jack 85 are duplicated so as tosupport the pipe length at spaced points between the pipe grips 43 onthe transport arm. The fixed jaws 82 are rigidly connected by a torquetube which can turn in the-outer end of the arm '67. q I I By control ofthe hydraulic jacks 64 and 71 the pipe gripping mechanism 72 on theupper arm '67 can be brought to any position within the confines of therack structure now to be described. This structure mounted on a base 91comprises two end sections 92 and 93 each having side walls 94 supportedby bracing struts 95. A plurality of vertical divisions 96 which areopen at the top are fixed in the end'sections 92'and 93 at aspacingwhich allows the pipe lengths to be stacked singly between them.The end sections 92 and 93 are spaced apart wider than the spacingbetween the two sets of jaws 82 and 83 on the arm 67 so that the lattercan move freely to any position to deposit a pipe in the rack structureor to take one away. The pipe lengths are deposited in the rackstructure in horizontal layers and taken away in like manner.

When running the string of drill pipe into a bore hole prior tocontinued drilling, the racking member formed by the arms 61, 67 andtheir actuating jacks together with the associated pipe grippingmechanism, is operable in reverse sequence to pick up pipe lengths oneat a time and transfer them to the transport arm 38 in the horizontalposition 38 of the latter as seen in FIGURE 2.

The transport arm 38 is of course reversible in its operation by thejack 42 to raise pipe lengths 24 one at a time into the verticalposition shown at which the pipe length can be taken over by thespin-off mechanism 13, between stages I and H in FIGURE 13.

I claim as my invention:

1. In combination, a derrick; a lift mechanism mounted in the derrick tobe raised and lowered in a vertical path, pipe gripping means on thelift mechanism to engage and support a string of pipe lengths in anupright disposition, means for operating the lift mechanism and the pipegripping means, to run in and pull the pipe string from and to anelevated upright position over the ground, respectively; a joinermechanism mounted on and raised and lowered with the lift mechanism, toattach and detach the pipe lengths to and from the pipe string, meansfor operating the joiner mechanism, to add and remove pipe lengths toand from the string in the elevated position; a first pipe transportmechanism mounted on and raised and lowered with the lift mechanism, tobe moved back and forth in a transverse path adjacent the elevatedposition, second pipe gripping means on the pipe transport mechanism toengage and support a pipe length in an upright disposition, means foroperating the pipe transport mechanism and the second pipe grippingmeans, to feed in and withdraw the pipe lengths from and to an outlyingupright position offset from the string, respectively; a second pipetransport mechanism pivotally mounted adjacent one side of the derrick,to be swung up and down in a vertical plane adjacent the outlyingposition, third pipe gripping means on the second pipe transportmechanism to engage and support a pipe length in an upright disposition,and means for operating the second pipe transport mechanism and thethird pipe gripping means, to feed up and lower the pipe lengths fromand to a substantially horizontal handling position on the side of thederrick, respectively.

2. The combination according to claim 1 further comprising anarticulated third pipe transport mechanism mounted adjacent the side ofthe derrick, to have one end thereof moved up and down, and to and fro,in a vertical plane adjacent the handling positon, fourth pipe grippingmeans pivotally mounted on the end of the third pipe transportmechanism, to engage and support a pipe length in a substantiallyhorizontal disposition, means for operating the third pipe transportmechanism and the fourth pipe gripping means, to unload and load thepipe lengths from and into a racked position on the side of the derrick,respectively, and means interconnecting the fourth pipe gripping meanswith the ground, to maintain the pipe lengths in a constant attitudewith respect to the latter, during the operation of the third pipetransport mechanism.

3. The combination according to claim 1 wherein the second pipetransport mechanism includes a transport arm which is pivotally mountedon the side of the derrick to be swung up and down in a vertical planeadjacent the outlying position.

4. The combination according to claim 1 wherein the first pipe transportmechanism is pivotally mounted on the lift mechanism to be swung backand forth in a transverse path adjacent the elevated position.

5. The combination according to claim 4 wherein the first pipe transportmechanism includes a spin-off mechanism that cooperates with the secondpipe gripping means.

6. The combination according to claim 5 wherein the joiner mechanismalso includes a make and break mechanism on the lift mechanism.

References Cited by the Examiner UNITED STATES PATENTS 1,900,921 3/33Endsley 175-85 X 2,531,930 11/50 Woolslayer et al 214-25 2,692,059 10/54Bolling 175-85 X 2,737,839 3/56 Paget 2l42.5 X 2,782,004 2/57 Harrigan29-427 2,956,782 10/60 Mistrot 17585 X CHARLES E. OCONNELL, PrimaryExaminer.

2O BENJAMIN BENDETT, Examiner.

1. IN COMBINATION, A DERRICK; A LIFT MECHANISM MOUNTED IN THE DERRICK TOBE RAISED AND LOWERED IN A VERTICAL PATH, PIPE GRIPPING MEANS ON THELIFT MECHANISM TO ENGAGE AND SUPPORT A STRING OF PIPE LENGTHS IN ANUPRIGHT DISPOSITION, MEANS FOR OPERATING THE LIFT MECHANISM AND THE PIPEGRIP PING MEANS, TO RUN IN AND PULL THE PIPE STRING FROM AND TO ANELEVATED UPRIGHT POSITION OVER THE GROUND, RESPECTIVELY; A JOINERMECHANISM MOUNTED ON AND RAISED AND LOWERED WITH THE LIFT MECHANISM, TOATTACH AND DETACH THE PIPE LENGTHS TO AND FROM THE PIPE STRING, MEANSFOR OPERATING THE JOINER MECHANISM, TO ADD AND REMOVE PIPE LENGHTS TOAND FROM THE STRING IN THE ELEVATED POSITION; A FIRST PIPE TRANSPORTMECHANISM MOUNTED ON AND RAISED AND LOWERED WITH THE LIFT MECHANISM, TOBE MOVED BACK AND FORTH IN A TRANSVERSE PATH ADJACENT THE ELEVATEDPOSITION, A SECOND PIPE GRIPPING MEANS ON THE PIPE TRANSPORT MECHANISMTO ENGAGE AND SUPPORT A PIPE LENGHT IN AN UPRIGHT DISPOSITION, MEANS FOROPERATING THE PIPE TRANSPORT MECHANISM AND THE SECOND PIPE GRIPPINGMEANS, TO FEED IN AND WITHDRAW THE PIPE LENGTHS FROM AND TO AN OUTLYINGUPRIGHT POSITION OFFSET FROM THE STRING, RESPECTIVELY; A SECOND PIPETRANSPORT MECHANISM PIVOTALLY MOUNTED ADJACENT ONE SIDE OF THE DERRICK,TO BE SWUNG UP AND DOWN IN A VERTICAL PLANE ADJACENT THE OUTLYINGPOSITION, THIRD PIPE GRIPPING MEANS ON THE SECOND PIPE TRANSPORTMECHANISM TO ENGAGE AND SUPPORT A PIPE LENGTH IN AN UPRIGHT DISPOSITION,AND MEANS FOR OPERATING THE SECOND PIPE TRANSPORT MECHANISM AND THETHIRD PIPE GRIPPING MEANS, TO FEED UP AND LOWER THE PIPE LENGTHS FROMAND TO A SUBSTANTIALLY HORIZONTAL HANDLING POSITION ON THE SIDE OF THEDERRICK, RESPECTIVELY.